BREEAM-NOR is a Norwegian adaptation of the international environmental rating tool BREEAM, considered the world's leading engineering and audit framework for sustainable buildings.

Buildings are classified into five BREEAM levels. "Outstanding" is the highest.

"A third party review has confirmed that Powerhouse Kjørbo is a world class project. As far as we know, this is the first rehabilitation project outside the UK to achieve the level of BREEAM Outstanding . We are very impressed," says Sverre Tiltnes of the Norwegian Green Building Council to the construction industry's online newspaper Bygg.no.

One of the main challenges Powerhouse Kjørbo had in meeting "BREEAM NOR Outstanding" was the short construction process. An important success factor was that BREEAM consultants were part of the project team from day one, and they also played an important role in documenting the environmental benefits of the building.

The Powerhouse partnership includes the aluminium company Hydro, the extrusion company Sapa, the property management firm Entra Eiendom, the construction company Skanska, the environmental organization ZERO, the architectural firm Snøhetta, and the consulting company Asplan Viak.